Godfrey DiGiorgi wrote on 4/5/2005, 1:57 PM:
> On Apr 5, 2005, at 10:39 AM, Village Idiot wrote: > > > I have questions about macro extension tubes. Does anyone use > > extension tubes? On what on what lenses do you usually use them? > > What is the difference between using extension tubes and using a macro > > lens? Also, why do extension tubes not work on DSLRs? hmmm missed the original post.... Anyway, Macro lenses have built-in extension and focus from very close to infinity. If you use extension tubes on any lens, you lose infinity focus. The one good thing about tubes is that you really don't need to worry about what brand you buy. Since there is no glass in them (they are just hollow tubes) you don't need to worry about them affecting image quality the same way a lens does (just make sure they are light-tight!). I use them a lot on my ist D. I have the Vivitar AF set which supports ALL functions necessary for automatic aperture control and autofocus just like the "A" lenses. I've used them on my 300/4 Sigma Macro to get just a little closer. I've used them on a vivitar 105mm macro for more than life-size images and I've used them with a 50mm both regular and reverse mounted. -- Christian [EMAIL PROTECTED]
